As others have said, don't rush to just acquire lenses. You have said you don't want to be redundant or make mistakes. Achieving that will come with using the lenses you have until you find their limitations and purchasing lenses that fit your needs. Don't worry about the "newest, bestest." I learned at, great cost, that a really good lens is timeless. My 28-70,17-35, 85, are from my days using film. They are still very good lenses.

Excellent advice, Rich. Although I am at a point where I do want to increase my lens collection, I want to do it gradually and smartly. Thus my posting of this thread, to get input from those who have gone through it all. Always learn from the mistakes of others! Although I cannot spend the money to get the lenses that are upwards of $2,000, I am going to buy the best I can.

So far, the advice I have received has been a big help. I decided that the lenses I have (18-105mm and 55-300mm) are fine for now, and that leaves me free to build my lens collection around them. Nothing is decided for sure yet, but so far I am leaning toward the following:

A good wide-angle for landscapes. Suggested was Nikon 10-24mm

A macro that can double as a portrait lens. Nikon 105mm

Much later, for wildlife/birds - Nikon 300mm f/4 + TC

Thinking about a fast prime for walk-around lens. Nikon 35mm f/1.8

Any comments/suggestions on this would be much appreciated. Thank you for your input.